Field of the Invention
The invention relates to a product label which is suitable in particular for a contactless identification of a product, such as during an inventory. The invention relates in particular to a product label which can be used for securing products and for theft prevention. The label is particularly secure against forgery.
U.S. Pat. No. 5,779,839 discloses product labels having a chip whose information can be sent to a reading device by using an antenna.
During the sale, the storage and the sorting of products and during the checking of product stocks, there are a large number of applications in which it is desirable for a product to be subjected to a specific processing operation only for a specific number of times and in particular only once. This applies in particular to the inventory of a stock of products or goods, in which a specific product is to be counted only once. In addition, at the checkout, the price for the product should be booked only once in the cash register. In the case of expensive products or goods, it is additionally common to provide the products with an anti-theft safeguard, which triggers an alarm when the business premises are left if the safeguard has not been removed. This is normally done at the cash desk, after the price for the products has been paid. In the case of the currently normal practice, however, the situation in which the anti-theft safeguard inadvertently remains on the product cannot be ruled out, in spite of the sales price having booked in the cash register and in spite of the products having been paid for.
A product label in which a tuned circuit is energized as it passes through a monitoring point is described in U.S. Pat. No. 5,142,270. The tuned circuit is provided with a predetermined breaking point, so that through the use of a surge of energy, the tuned circuit can be destroyed and the label becomes ineffective. The label does not contain any information about the products.